1. Field of the Invention
The invention relates to an image recording apparatus and, more particularly, to an ink jet recording apparatus for recording by discharging ink from recording means which has removably been attached onto a carriage which is movable along a recording medium.
2. Related Background Art
In recent years, image information can be easily handled owing to the spread of personal computers, digital cameras, and the like and a demand for an easy-to-use recording apparatus as an output apparatus is increasing. Among recording systems which are used for the recording apparatuses, there is an ink jet recording system known as a relatively small and reasonable system which enables fine recording.
In the recording apparatus using the ink jet recording system, a carriage on which recording means (a recording head or a head cartridge in which the recording head and an ink tank unit are integratedly assembled) having tens to hundreds ink discharge ports has been attached is constructed so that it is coupled with a part of a driving belt for transferring a driving force of a carriage driving motor and is movable.
According to the above structure, the recording means can be moved along a platen arranged so as to face the discharge surface and, during the movement, the recording means moves (scans) reciprocatively the whole width of the recording medium (medium to be recorded) which is conveyed on the platen, thereby enabling the recording to be executed. The recording medium is conveyed by conveying means every scan of the carriage by a distance which is determined in accordance with a pitch of the discharge ports. The recording is executed onto the whole surface of the recording medium by repeating the above-mentioned scan and conveyance of the recording medium.
Among the ink jet recording apparatuses in which the head cartridge is removably attached onto the carriage, there is an apparatus constructed in such a manner that when the ink in the head cartridge is fully consumed or when the head cartridge fails, it is replaced by a new head cartridge, thereby enabling the recording apparatus to be easily recovered to a recording possible state. Among the recent ink jet recording apparatuses having the advanced functions, an ink jet recording apparatus constructed in such a manner that by replacing a regular head cartridge for monochromatic printing by an optional head such as a head cartridge for photo-printing or the like, a photo-image of a photographic tone or the like can be recorded has also been spread.
In the conventional carriage structure, in order to electrically couple the head cartridge with the recording apparatus main body, a board (head board) having a conductor exposing portion onto which ‘regist’ is not applied or a flexible printed circuit board (FPC) is provided on the head cartridge side. There are many cases where a pressure contact connector to electrically couple the head cartridge with the conductor exposing portion of the head cartridge is provided for the carriage to attach (or mount) the head cartridge. The pressure contact connector is ordinarily formed by plating a metal and is come into pressure contact with the conductor exposing portion of the head cartridge by using an elastic deformation of the metal. Further, the pressure contact connector is soldered to a board (carriage board) attached in the carriage. Moreover, the board on the carriage is electrically coupled with a circuit board (control circuit) of an apparatus main body side through a flexible flat cable (FFC), the FPC, or the like.
As a foregoing related art, a structure in which a fixing member for fixing the recording means enclosed in the carriage is rotatably provided for the carriage and an operating unit which applies a force to rotate the fixing member is provided for the fixing member has been disclosed in Japanese Patent Application Laid-Open No. 2004-090343. However, in order to press the recording means to the pressure contact connector of the carriage, a large force is necessary in dependence on the number of electrical contacts between the recording means and the carriage. Thus, when the recording means is attached to the carriage, a very large operating force is needed. Therefore, in order to prevent the deformation of the fixing member for fixing the recording means to the carriage, it is necessary that a special material having high rigidity is used for a mechanical portion of the fixing member, or in order to reduce the operating force of the fixing member, it is necessary to use a complicated link mechanism.
In the conventional recording means such as a head cartridge or the like and the attachment fixing structure to a plurality of recording means enclosing portions provided for the carriages in order to attach the recording means, each recording means has substantially the same external shape and a color indication is provided on the recording means, thereby paying attention to the user so as to attach the recording means of a predetermined color to a predetermined position of such a structure. However, if such a construction is merely used, there is such a problem that, according to the attachment fixing structure to a plurality of recording means enclosing portions provided for the carriages, the situation where the recording means of the wrong color is attached cannot be completely prevented and there is a troublesomeness upon recording.
To solve such a problem, in U.S. Pat. No. 5,519,422, there has been disclosed a construction in which projections such as tabs, wings, or the like of different positions or different numbers are provided for the recording means, and in a plurality of recording means enclosing portions provided for the carriages of the recording apparatus main body, the erroneous attachment of recording means out of the standard is prevented by changing a size or a position of a barrier provided in a bottom portion of each enclosing portion.
According to the construction disclosed in Japanese Patent Application Laid-Open No. 2004-090343, when the recording means is replaced, it is necessary to insert it into the carriage from an upper direction of the recording apparatus main body. Since the operating unit is provided for the fixing member of the recording means, the user fixes the recording means to the carriage in a pressing state by rotating the fixing member together with the operating unit. In such a case, it is necessary to sufficiently widely assure a space where the recording means can pass or a space where the operating unit rotates by opening a cover in an upper portion of the apparatus main body.
Further, in recent years, an apparatus such as an ink jet hybrid apparatus (multi-function printer: MFP) in which an ink jet recording apparatus and a flat bed scanner are combined and a copy or the like of an original sheet (or paper) can be performed has also been wide-spread. In such a multi-function printer, since an original sheet reading unit is provided in an upper portion of the recording apparatus, when the recording means is attached onto the carriage, it is necessary to insert the recording means into a deep position of the apparatus while it is sandwiched, so that there is a problem that the operation of the user is troublesome. In such a problem, to improve the operability of the user, an opening portion of the apparatus main body from which the user accesses the carriage has to be widened by increasing the whole recording apparatus.
Further, according to such a construction, since it is necessary to grasp the recording means until it is certainly attached onto the carriage, if the user erroneously operates, there is a fear of dropping of the recording means. Also, when the recording means is attached/removed to/from the carriage, if the user does not certainly grasp the recording means, he will drop it. Since the ink discharge portion of the ink jet recording head is very delicate and clogging or a damage is liable to occur, not only the recording head is broken by the drop of the recording means but also it cannot be used due to a deposition of dust or the like. It is, therefore, an important subject to prevent the drop of the recording means which is caused when the user executes the attaching/removing operation to/from the apparatus main body.
Since the apparatus disclosed in Japanese Patent Application Laid-Open No. 2004-090343 has the construction in which the recording means is inserted into the carriage from almost the upper direction of the recording apparatus main body, even if the wrong carriage is inserted into the recording means enclosing portion, it is kept placed on the carriage due to an own weight of the recording means itself. Thus, the carriage executes the operation similar to that in the case where the recording means is not attached, so that a maintenance unit of the recording means is carelessly made dirty, the recording means or the recording apparatus main body is electrically short-circuited, or the recording means or the recording apparatus is broken by the unreasonable scan of the carriage.
Further, in the case of the ink jet multi-function printer which has been wide-spread in recent years as mentioned above, since it is inevitably necessary to attach the recording means onto the carriage arranged in the deep position of the apparatus, it is very difficult for the user to confirm by the eyes whether or not the recording means has correctly been attached. For example, even if the user tries to discriminate about the correct/erroneous attachment of the recording means by a tactile sensation of the hand by which the recording means has been inserted, particularly, in the case where he attaches the recording means for the first time, the correct attaching position to the carriage is obscure, and thus there is such a problem that it is difficult for the user to discriminate whether or not the recording means has correctly been attached.
It is, therefore, an important subject to prevent the erroneous attachment at the time of the attaching/removing operation of the recording means to/from the apparatus main body and enable the user to easily discriminate the correct/erroneous attachment of the recording means.